Rear Windows: No power

bavbob

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My 73 (June 73) E9 rear window regulators are the newer type and work perfectly when I hook a 12V source directly to the motor. However, no go when I turn the ignition and then try to run them with the rear switches. I have a single window relay up front that locks in place but is fairly crusty. I also have the switches at the center console disconnected. All fuses intact, cleaned the fuse box too. So..
1) I assume I can just bypass the relay without any repercussions by joining the two wires that go to it and thereby identify or eliminate it at a source of the problem?
2) Why do I think I need to install the switches in the center console before the rear switches will work....
 

Ohmess

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Power is daisy chained from the center console switches to the rear switches; rear switches will not operate without the center switches in the circuit.
 

adawil2002

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The rears are a 3-way switch, meaning they can be operated by the front-rear switch & the rear side arm rest switch for both up & down operation. The front-rear switches have 3 wires & the rear arm rest have 2 wires. I do not have any photos of which wire goes to which switch tab. I figured it out through trial & error back in 2011.
 

bavbob

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Is there a way to jump the terminals at the front switch so I can get continuity without the switch.?
 

rsporsche

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the rear console switches are powered from fuses 8 + 9 (green / blue wire). this switch sends a green / blue wire to the front switch - which then sends power to the rear (side) switch (again green / blue wire). each rear switch sends power to the motor via a green / yellow wire. the rear wires are joined together at the junction block (prior to the motor). the other side of the switch is a black / red wire ... again joined at the junction block. i presume that the green / yellow lowers the window and the black / red raises it (i could have this backwards).
 

rsporsche

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IMG00136-20110424-1137.jpg
 

rsporsche

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Is there a way to jump the terminals at the front switch so I can get continuity without the switch.?
not sure i follow you. power should flow to all switches (starting at the rear console switch) then flowing to the front console switch ... then from there back to the rear side switch. this doesn't really act like a true 3 way switch. as power flows and joins at the junction block prior to the motor. check the junction block that all wires are connected there.

in the wiring diagram below, 72 is the left front window switch / 79 is left front motor. 92 is the left rear console window switch / 87 is the left rear side window switch / 86 is the junction block / 88 is the left rear motor.
 

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bavbob

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Scott, do you have the diagram for a Euro? My wiring is nothing like that in the diagram.
I have only electric rear windows, manual fronts. Center console switch shows 11.5V while rear when switched, shows only 4.5V at the motor. Even when center console switch is removed, still get 4.5 V to motor when I depress the rear switch. I see no junction block. I have a drop in voltage but there is nothing between the front console and loom that goes to the rear window switch and the problem exists on both sides.
 

rsporsche

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the rear junction block is at the window frame (behind the rear arm rest). the wiring diagram i have for non-USA is not very clear

i presume that the wiring would be similar - just the feed to the side switch would come directly from the console switch ... whether it is plugged into the switch or not as the circuit is branched before it is plugged into the switch. once either switch is moved to one side it powers the motor (thru the junction block)

e9 window wiring - non usa.jpg
 
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